JP6740245B2 - Razor blade - Google Patents

Description

The present invention relates to razors, and more particularly to razor blades in which the cutting area of the razor blade is profiled.

In particular, the invention relates to razor blades. Blade shape plays an important role in shaving quality. The blade typically has a continuously tapered shape that converges toward the leading edge. The portion of the blade closest to the leading edge is called the tip edge.

A tougher tip edge will result in less wear and a longer service life, but at the expense of higher cutting forces, which can adversely affect shaving comfort. A thin tip edge profile provides a small cutting force, but an increased risk of breakage or damage and a short service life. Therefore, a razor blade edge that provides an optimal trade-off between cutting force, shaving comfort, and service life is desirable.

To achieve the above objectives, the cutting edge of a razor blade is shaped, which shaping is the result of grinding.

Historically, there have been numerous patents relating to the geometry of certain parts of the blade. A typical example is U.S. Pat. No. 6,037,049 from 1971, which focuses on the cutting edge geometry of the blade. U.S. Pat. No. 6,037,086 precisely defines the geometric shape from the tip to 8000 Angstroms, or 0.8 micrometers. This geometry is mostly associated with the blade entering the inside of the hair to be cut (hair diameter is typically on the order of 100 micrometers).

Few documents provide an overall view of the overall blade geometry. One of these documents is US Pat. US Pat. No. 6,037,058 first describes a prior art geometry that uses both numerical data and an included angle of 19°.

Compared to its prior art, the object of the invention of US Pat. No. 6,037,049 is thinner at the first 100 micrometers from the tip and includes an included angle of 12° to 17° further away from the tip.

Another document with a holistic approach is US Pat. This document provides an overview of the blade geometry in its first figure. Similar to the above technique, Patent Document 3 also shows an included angle of 14° or 12°. However, very little is described about this figure, and Ref. 3 is primarily concerned only with geometries up to 100 micrometers from the tip. The detailed description is inconsistent with this figure and refers to angles of 9° to 11.5°, and in some cases expandable 7° to 14°, taking into account manufacturing variations. U.S. Pat. No. 5,837,837 has a more mathematical approach and defines two regions of interest having different types of geometric shapes. From 40 to 100 micrometers from the tip, the geometry of the edge is defined by the included angle, so that up to 40 micrometers from the tip, the geometry of the tip of the edge is of the hyperbolic type w=ad ⁿ . It is defined by a mathematical expression, the value of the parameter “a” is unspecified (less than 0.8), and the parameter “n” is 0.65 to 0.75. Prior art blades to Patent Document 3 are said to exhibit a value of "n" greater than 0.76.

US Pat. No. 6,096,697 insisted that the state-of-the-art shape be improved by another hyperbolic equation to improve this shape from the tip to 5 micrometers.

Many publications primarily refer to the shape of the coated blade without detailing the shape of the underlying substrate or simply by defining the included angle. U.S. Pat. No. 5,697,097 discloses that a sharp tip comprises adjacent facet shaving surfaces having an included angle of 15-30 degrees, preferably about 19 degrees measured at 40 microns from the sharp tip. By disclosure, such a razor blade has already been described. However, this cutting edge structure only discloses a constant facet convergence towards the tip of the blade.

Recently, in US Pat. No. 6,037,639 a razor blade with a “thinner” edge is advertised. This reference gives the size range of the blade geometry for 16 microns from the tip. There seems to be some overlap between these data and the set of parameters disclosed in the previous literature. Moreover, this document does not mention anything about the geometry of the blade beyond 16 micrometers from the tip.

Although Applicants believe that a thinner edge tip on the blade provides certain benefits, it may be possible to weaken such an edge, as discussed above, and thus define this geometry. That is not enough. Moreover, as mentioned above, some general geometries of razor blades are known that have a particular surface starting about 40 micrometers from the tip. Which of these geometries is suitable for the tip of a thinner blade edge is not straightforward, especially since the exact disclosure of US Pat. Accordingly, Applicants have been conducting intensive research to determine blade characteristics that may be beneficial in seeking thinner edge geometries as a whole.

Enhancing the properties of a razor blade is a very difficult process. First, the blades are manufactured using a very high throughput (millions of products per month) industrial process. Such industrial processes are not invariant, and there are product-to-product variations that must be kept within reasonable limits. Secondly, in order to see if the new razor blades offer improved performance, tests simulating shaving must be performed, the results of which are correlated with the characteristics of the razor blade. There must be.

With respect to razor blade geometry, it is quite difficult to measure small features with sufficient accuracy for complex shapes such as razor blade edges. One known method for measuring the edge geometry of a blade is the so-called scanning electron microscope (SEM). SEM is performed on the cross section of the blade. Since it is essential to prepare the cross section of the razor blade, there is now the question of whether the SEM can provide relevant measurement data. The preparation of the sample to be imaged is rather difficult, so only a few samples can be imaged and the results are not statistically meaningful.

Other methods for measuring blade geometry include interferometry and confocal microscopy. Both can be used non-invasively and address the issues listed above for SEM. However, due to the different approaches, these two methods provide different results. In addition, variability in the measurement method must also be taken into account when evaluating the measurement results.

It is believed that, following extensive testing, confocal microscopy can provide the most accurate measurements for manufactured razor blades. Unless otherwise stated, all geometric data provided later in this specification has been obtained using this method.

U.S. Pat. No. 3,835,537 British Patent Application Publication No. 1465697 European Patent No. 0126128 International publication 2003/006218 pamphlet European Patent No. 1259361 European Patent No. 2323819

It is an object of the present invention to provide a razor blade suitable for a shaving head of a shaver, which reduces the wear of the razor blade and further extends its life while at the same time the cutting force is at least known As small as in the member, shaving comfort is at least as high as in known cutting members.

To this end, according to the invention, there is provided a razor blade substrate having a symmetrical tapered edge that terminates in a sharp tip, the substrate being measured at a distance of 5 micrometers from the tip. Measured at a thickness of 1.55 to 1.97 micrometers, measured at a distance of 20 micrometers from the tip, measured at a thickness of 4.60 to 6.34 micrometers, measured at a distance of 100 micrometers from the tip It has a continuously tapered geometry with a thickness of 19.80 to 27.12. Unless otherwise specified, all blade edge measurement data claimed is obtained through confocal microscopy.

In order to define a properly supported thin edge tip, it is essential to define the profile geometry at the particular concrete keypoints claimed above, which results in an edge tip that results in The resulting edge geometry and thickness over the 20 μm region from the leading edge provide a low cutting force and a sufficient service life, thus offering an optimal trade-off in shaving performance in terms of comfort. Turned out to provide.

According to one aspect, the substrate has a thickness of 6.50-8.94 micrometers measured at a distance of 30 micrometers from the tip.

According to one aspect, the substrate has a thickness of 8.40-11.54 micrometers measured at a distance of 40 micrometers from the tip.

According to one aspect, the substrate has a thickness of 10.30 to 14.13 micrometers measured at a distance of 50 micrometers from the tip.

According to one aspect, the substrate has a thickness of 29.30-40.11 micrometers measured at a distance of 150 micrometers from the tip.

According to one aspect, the substrate has a thickness of 38.80 to 49.74 micrometers measured at a distance of 200 micrometers from the tip.

According to one aspect, the substrate has a thickness of 48.30 to 59.37 micrometers measured at a distance of 250 micrometers from the tip.

According to one aspect, the substrate has a thickness of 57.80-69.00 micrometers measured at a distance of 300 micrometers from the chip.

According to one aspect, the substrate has a thickness of 67.30 to 78.62 micrometers measured at a distance of 350 micrometers from the tip.

According to one aspect, the razor blade substrate has a thickness of 1.80 to 1.95 micrometers measured at a distance of 5 micrometers from the tip.

According to one aspect, the razor blade substrate has a thickness of 5.40-6.30 micrometers measured at a distance of 20 micrometers from the tip.

According to one aspect, the razor blade substrate has a thickness of 7.00 to 8.00 micrometers measured at a distance of 30 micrometers from the tip.

According to one aspect, the substrate has a thickness of 9.20-10.70 micrometers measured at a distance of 40 micrometers from the tip.

According to one aspect, the razor blade substrate has a thickness of 11.20 to 13.10 micrometers measured at a distance of 50 micrometers from the tip.

According to one aspect, the razor blade substrate has a thickness of 23.00 to 25.10 micrometers measured at a distance of 100 micrometers from the tip.

According to one aspect, the razor blade substrate has a thickness of 32.30 to 37.10 micrometers measured at a distance of 150 micrometers from the tip.

According to one aspect, the razor blade substrate has a thickness of 41.00 to 47.30 micrometers measured at a distance of 200 micrometers from the tip.

According to one aspect, the razor blade substrate has a thickness of 51.40-56.50 micrometers measured at a distance of 250 micrometers from the tip.

According to one aspect, the razor blade (razor blade) substrate has a thickness of 61.00 to 65.40 micrometers measured at a distance of 300 micrometers from the tip.

According to one aspect, the razor blade substrate has a thickness of 70.40-76.10 micrometers measured at a distance of 350 micrometers from the tip.

According to one aspect, the thickness of the substrate cutting edge is described by the following equation:

Here, in the formulas A and B, a and c are constants from the interval (0, 1), b is a constant from the interval (0.5, 1), and d is the interval (0.5, 20). ), x refers to the distance from the tip in micrometers, t refers to the thickness of the blade in micrometers, equation A applies from the tip to the transition point, and equation A or equation B Either applies to the other place.

According to one aspect, the substrate comprises most iron by weight,
-0.62-0.75% carbon,
-12.7 to 13.7% chromium,
-0.45-0.75% manganese,
-0.20 to 0.50% silicon, and-inevitable impurity level molybdenum,
Is stainless steel containing.

According to one aspect, the substrate is covered by a reinforcing coating.

According to one aspect, the reinforcing coating comprises titanium and boron.

According to one aspect, the substrate is covered by an intermediate layer and the intermediate layer is covered by said reinforcing layer.

According to one aspect, the reinforcing layer is covered by the top layer.

According to one aspect, the top layer is covered by a polytetrafluoroethylene layer.

According to some particular embodiments, a range of thicknesses at a distance of 50-350 μm from the tip is satisfied in order to achieve the desired geometry for shaving comfort and blade durability. It's important to.

Other features and advantages of the present invention will be readily apparent from the following description of some of its embodiments, provided by way of non-limiting example, and the accompanying drawings.

FIG. 4 is a state-of-the-art profile view of the razor blade of the present invention. FIG. 3 is a view of a profile of a cutting edge of a razor blade of the present invention. FIG. 5 is a view of a profile of a cutting edge of a razor blade covered by a coating layer. FIG. 5 is a view of the profile of the cutting edge of a razor blade covered by the coating layer of the present invention. FIG. 7 is a diagram of confocal measurement settings. It is a figure of a grinder. It is a figure of a grinder. FIG. 6 is a cross-sectional view of one embodiment of a razor. FIG. 6 is a cross-sectional view of one embodiment of a razor.

In the different drawings, the same reference signs indicate similar or identical elements.

The desired blade profile can be achieved by a grinding process that includes two, three or four grinding stations. FIG. 6 illustrates a grinding installation 1 having two stations 2a and 2b. The substrate is a continuous strip 3. The continuous strip 3 consists of the raw material for the substrate of the razor blade, which substrate has previously been subjected to a suitable metallurgical treatment. This is, for example, stainless steel. It is also believed that the present invention is applicable to razor blades having a carbon steel substrate. Another material is ceramics. These materials are currently considered suitable for razor blade materials. The metal strip is longer than a plurality of razor blades and accommodates, for example, 1000 or more razor blades. Prior to grinding, the metal strip 3 has a generally rectangular cross section. The height of the metal strip can be slightly above the height of the finished razor blade, or slightly above the height of the two finished razor blades if grinding is done on both edges. .. The thickness of the metal strip is the maximum thickness of future razor blades. The strip may be provided with a through punch, which may convey the strip along the installation 1 during the grinding process and/or facilitate the future separation of individual razor blades from the strip. Can be used to

As the metal strip 3 moves along the grinding stations 2a, 2b, the metal strip 3 is sequentially subjected to rough grinding, semi-finishing and finish grinding. Depending on the number of stations involved, the rough grinding and semi-finishing operations can be done separately or in the same station. Thereafter, a finish grinding operation may be required. The grinding step is performed continuously and the strip moves continuously through the station without stopping.

If the rough grinding is done separately, then one or two grinding stations are required. Each grinding station can use one or two polishing wheels arranged parallel to the moving strip. The polishing wheel has a uniform grit size along its length. They may also be grooved along their length, either in full body or in a spiral. The material of the polishing wheel is resin-bonded or vitrified diamond, resin-bonded or vitrified CBN (Cubic Boron Nitride), or resin-bonded or vitrified silicon carbide, aluminum oxide. Particles or mixtures of the particles mentioned above can be used.

If the rough grinding and semi-finishing operations are performed simultaneously, then a single grinding station is required for these operations. In this case, this station comprises two grinding wheels formed in a spiral structure or a series of linear discs with a special profile. The axes of rotation of these wheels may be parallel to the moving strip or may be arranged at a predetermined angle of α1. The tilt angle is in the range of 0.5 to 2 degrees. Also, the grit size of the wheel may be uniform or it may decrease gradually along the length of the strip towards the outlet of the strip. The material of the polishing wheel is resin-bonded or vitrified diamond, resin-bonded or vitrified CBN (cubic boron nitride) or resin-bonded or vitrified silicon carbide, aluminum oxide or a mixture of these particles. Can be used.

The finishing operation requires a single grinding station with two polishing wheels arranged at an angle to the moving strip. The inclination angle α2 is opposite to the inclination angle used for rough grinding. The inclination angle is in the range of 1 to 5 degrees. The wheels form a spiral structure and are specially contoured. The abrasive can be a single or polycrystalline grain material of CBN, silicon carbide, aluminum oxide or diamond as described above.

The process is tailored to obtain a symmetrical razor blade substrate 10 having a continuously tapered geometry as shown in FIG.

Confocal microscopes have been used for measuring blade geometry, surface roughness and grinding angles. A typical example is shown in FIG. The confocal microscope includes an LED light source 21, a pinhole plate 22, an objective lens 23 having a piezo drive device 24, and a CCD camera 25. The LED light source 21 is focused on the surface of the sample 26 that reflects light through the pinhole plate 22 and the objective lens 23. The reflected light is weakened by the pinhole of the pinhole plate 22 to the in-focus portion, and goes to the CCD camera. The sample 26 shown here does not show a razor blade. A razor blade is used with the sides angled with respect to the focal axis of the lens passing through the lens 23 in the device. The confocal microscope has a given measurement area of, for example, 200 μm×200 μm. In this example, a semitransparent mirror 28 is used between the pinhole plate 22 and the lens 23 to guide the reflected light to the CCD 25. In this case, another pinhole plate 27 is used for filtering. However, in a variant, the semi-transparent mirror 28 can be used between the light source and the pinhole plate, so that only one pinhole plate for both the emitted light signal and the reflected light signal can be used. To

The piezo drive 24 is adapted to move the lens 23 along the propagation axis of the light to change the focus position in depth. The focal plane can be varied while maintaining the dimensions of this measurement area.

To extend the measurement area (especially to measure the edge of the blade farther away from the tip), another measurement can be made at another location and the data from all the measurements are summarized ( stitch).

The other side of the blade can then be measured by simply flipping the blade over to the other side.

According to one example, a confocal microscope based on confocal multi-pinhole (CMP) technology can be used.

The pinhole plate 22 then has a large number of holes arranged in a special pattern. The movement of the pinhole plate 22 allows a seamless scanning of the entire surface of the sample in the image field so that only the light from the focal plane reaches the CCD camera with an intensity that follows the confocal curve. Therefore, the confocal microscope is capable of high resolution in the nanometer range.

Also, other methods can be used to measure the thickness of the razor blade, for example, the cross section of the blade can be measured by scanning electron microscopy (SEM). SEM is performed on the cross section of the blade. Since it is now essential to create a cross section of a razor blade (razor blade), it is doubtful whether the SEM can provide meaningful measurement data. The preparation of the samples to be imaged is rather difficult, so very few samples are imaged and the results may not be statistically significant.

Further, the blade thickness can be measured by an interferometer. For this measurement, a white light probe from one of various light sources (halogen, LED, xenon, etc.) is coupled to an optical fiber in the controller unit and sent to the optical probe. The emitted light undergoes reflection from the blade and is collected back into the optical probe, back-flowing through the fiber and collected in the analysis unit. The modulated signal is fast Fourier transformed to provide a thickness measurement. However, since this measurement is based on the interference of light from the surface of the blade, the thickness measured by this method can be adversely affected.

In order to confirm the reproducibility of the measurement method described above, the same blade measurement using the same method was performed by different operators at different times. This was done for many blades. Confocal microscopy has been shown to provide much better repeatability and reproducibility than interferometry.

In order to be able to determine the exact thickness of the cutting edge, several measurements were made on some blades by the measuring method described above. The average results of these measurements are shown in Table 1 below.

From Table 1 above, it is clear that the interferometric measurement results differ from the confocal microscopy results. Therefore, also in view of the better reproducibility of measurements using confocal microscopy as described above, in the discussion of dimensions below, dimensions will be referred to as those of the above, unless the context clearly indicates otherwise. It has been obtained by measurement using focus microscopy.

A razor blade according to the present invention comprises a sharpened blade substrate 10. The blade substrate 10 has a flat portion 8 and the two opposite sides of the blade are parallel to each other. In addition, the blade substrate also comprises a cutting edge portion 11 shown in cross-section in FIGS. 1 and 2 which is connected to the flat surface portion 8, the side surfaces 12, 13 of which are tapered and , Converges at the substrate tip 14 of the blade tip portion 11. The thickness of the cutting edge portion 11 can be measured by a confocal microscope. The shape of the blade is contoured, ie the cross section of the blade is substantially the same along the length of the blade.

Razor blades with various geometries have been manufactured, measured, and tested for shaving performance. Manufacturing includes not only substrate sharpening by grinding, but also coatings as described below. For the shaving test, only the grinding step was modified to produce various substrate geometries, the other process steps were kept the same.

The test determined that the thinness of the tip edge can be defined by examining the thickness of control points located 5 and 20 micrometers from the tip. Further, the strength of the tip of the edge can be defined by checking the thickness of control points located at 20 and 100 micrometers from the tip.

Furthermore, the dimensions given here are the average dimensions along the length of the blade. Due to the manufacturing process, a single blade will not have exactly the same profile along its entire length. Thus, each thickness value is an average of various data obtained along the length, eg, 4-10 data.

After rigorous testing it was found that a favorable shaving effect was obtained for a shaving blade with the following characteristics:
The cutting edge portion 11 of the blade has a thickness T5 of 1.55 to 1.97 micrometers measured at a distance D5 of 5 micrometers from the tip.
The cutting edge portion 11 of the blade has a thickness T20 of 4.60 to 6.34 micrometers measured at a distance D20 of 20 micrometers from the tip.
The cutting edge portion 11 of the blade has a thickness T100 of 19.80 to 27.12 micrometers measured at a distance D100 of 100 micrometers from the tip.

The dimensions described above can be obtained through the distribution of products manufactured using the same manufacturing process.

The blade has a smooth profile between these control points and beyond them (both from the tip and away from the tip). The preferred results of the above technique are as listed in Table 2 below (although the measured thickness geometry at other checkpoints is not considered relevant for product quality qualification). It had the following profile:

More preferably, the thickness of the cutting edge 11 of one of the above-described embodiments has the following thickness configuration. The thickness T5 is 1.80 to 1.95 micrometers measured at a distance D5 of 5 micrometers from the tip. The thickness T20 is 5.40-6.30 micrometers measured at a distance D20 of 20 micrometers from the tip. The thickness of T100 is 23.00-25.10 micrometers measured at a distance D100 of 100 micrometers from the tip.

In such a case, the thickness configuration is detailed in Table 3 below.

Examples of particular embodiments of the invention have the following thickness configurations as detailed in Table 4 below.

The rate of increase of blade thickness from the tip to the transition point (slope) should decrease continuously, thereby making it easier for the edge of the blade to penetrate into the hair, resulting in better comfort. The profile of the blade behind the transition point (40 μm to 350 μm) should be in a certain range of values to support a geometrically smooth transition from the initial 40 μm to the unground portion of the blade. is there. In that region, the rate of increase in thickness is less than or equal to the rate of increase at 40 μm.

The edge profile of the blade produced by the rough grinding step typically occupies a region of 50-350 μm from the tip and determines the material removal rate of the finishing operation. Generally, the finish grinding step is considered to smooth the excess surface roughness created by rough grinding, along with the final shaping of the edge profile of the blade. For optimum processing efficiency, the material removal rate of the finish grinding wheel should be kept to a minimum, but the induced surface roughness should be kept in the range of 0.005-0.040 μm. ..

For example, the thickness of the aforementioned blade profile can be described by the following equation:

In the above equation, a and c are constants from the interval [0,1], b is also a constant from the interval [0.5,1], and d is from the interval [0.5,20]. Is a constant, x is the distance in micrometers from the tip, and t is the thickness of the blade in micrometers.

One or more equations (A) can be applied in turn to the portion of the blade extending from the tip to the transition point, and one or more equations (B) can be applied from the transition point to the unground portion of the blade. It can be applied to each.

For some embodiments, equation (A) describes a tip thickness of 0-40 micrometers from the tip. For example, the constants a=0.5 and b=0.8. Expression (B) describes the thickness of the cutting edge from 40 to 350 micrometers from the tip, and the constants c=0.2 and d=1.5.

According to the second embodiment of the present invention, the thickness of the cutting edge 11 of the blade has the following thickness configuration, as detailed in Table 5 below.

Furthermore, the thickness of the profile of the above-mentioned blade can be described by the above-mentioned mathematical expressions (A) and (B).

For the second embodiment, equation (A) describes a cutting edge thickness of 0-20 micrometers, with constants a=0.47 and b=0.84. Equation (B) describes a cutting edge thickness of 20 to 150 micrometers, with constants c=0.251 and d=0.800. Furthermore, equation (B) describes a thickness of the cutting edge of 150 to 350 micrometers, with constants c=0.1775 and d=11.8750.

According to the third embodiment of the present invention, the thickness of the cutting edge 11 of the blade has the following thickness configuration, as detailed in Table 6 below.

Further, the thickness of the blade profile described above can be described by the above equation (A).

For the third embodiment, equation (A) describes a cutting edge thickness of 0 to 20 micrometers, with constants a=0.45 and b=0.79. Furthermore, equation (A) describes a cutting edge thickness of 20 to 350 micrometers, with constants a=0.296, b=0.93.

According to the fourth embodiment of the present invention, the thickness of the cutting edge 11 of the blade has the following thickness configuration, as detailed in Table 7 below.

Further, the thickness of the blade profile described above can be described by the mathematical formulas (A) and (B) described above.

For the fourth embodiment, equation (A) describes a cutting edge thickness of 0 to 20 micrometers, with constants a=0.54 and b=0.80. Further, the formula (A) describes the thickness of the cutting edge of 20 to 200 micrometers, and the constants a=0.40 and b=0.90. Equation (B) describes a cutting edge thickness of 200 to 350 micrometers, with constants c=0.18 and d=11.10.

All of the above-described embodiments of the razor tip and cutting edge of the present invention may be described by equation (A) and equation (B), or a combination of both equations. Equations (A) and (B) describe different cross sections measured from the razor tip 14.

The razor blade substrate 10 with the razor blade edge 11 is made of stainless steel. The preferred stainless steels are primarily iron and -0.62-0.75% carbon by weight-12.7-13.7% chromium-0.45-0.75% manganese-0.20. 0.50% silicon-with trace amounts of molybdenum.

Other stainless steels can be used within the present invention. Other materials known as substrates for razor blades can be considered.

Further manufacturing steps for the razor blade are described below.

A blade substrate 10 with a cutting edge 11 having a contoured geometry and a tapered geometry with two substrate sides 12, 13 converging towards a substrate tip 14 is , At least at the edge of the blade, covered by a reinforcing coating 16 deposited on the razor blade substrate. The coating layer is applied on the edge substrate of the blade to improve the hardness of the edge of the blade and thereby improve the quality of the shave.

The coating layer reduces blade edge wear, improves overall cutting characteristics, and allows extended razor blade usability.

The reinforcing coating 16 over the substrate tip 14 has a contoured geometry and a tapered geometry with two coating sides that converge toward the coating tip. In FIG. 3, the blade edge substrate 10 is coated with a reinforcing coating layer 16 and a lubricating layer 17. The lubricious layer can comprise a fluoropolymer and is commonly used in the razor blade art to reduce friction during shaving. The reinforcing coating layer 16 is used because of its mechanical properties. The reinforcing coating layer 16 can include titanium and boron. More precisely, the reinforcing coating layer 16 can be made of titanium and boron with a low content of impurities. The content of impurities is kept as low as economically feasible. The reinforcing coating layer 16 can be prepared with various proportions of titanium and boron in the layer. Other embodiments may comprise a mixture of chromium and carbon, DLC, amorphous diamond, or others. Furthermore, the cutting edge 11 of the blade can be covered by the intermediate layer 15. For example, the intermediate layer 15 preferably consists of titanium, especially in the case of titanium and boron containing reinforcing coatings. If the blade is covered with a titanium intermediate layer 15, the intermediate layer 15 is applied before the reinforcing coating layer 16. As described above, the coating layer of the blade edge 11 of the blade includes the Ti intermediate layer 15 that covers the blade edge 11 of the blade and the reinforcing coating layer 16 that covers the Ti intermediate layer 15. Further, the reinforcing coating layer 16 can be covered by the top layer 20. An example of a top layer is a top layer that contains chromium, especially consisting of chromium. The top layer 20 containing chromium can also be covered by a lubricating layer 17, which can comprise a fluoropolymer, as shown in FIG.

The blade can be fixed to or mechanically assembled to the razor head, and the razor head itself can be part of the razor. The blade may be movably mounted on the razor head and may be mounted on a spring that presses the razor head towards a rest position. The blade can be fixed, in particular welded to the support 29, and can be welded to a metal support having a cross section, in particular an L-shaped cross section, as shown in FIG. 8a. Alternatively, the blades can be integrally curved blades, as shown in FIG. 8b, and the geometry disclosed above allows for a between the blade tip and the curved portion 30. Applied.

10 Substrate 11 Cutting Edge 14 Tip 15 Intermediate Layer 16 Reinforcement Coating 20 Top Layer

Claims (14)

A razor blade comprising a substrate (10) having a symmetrical tapered edge (11) terminating in a sharp tip (14),
The substrate was measured at a distance of 5 micrometers from the tip (D5), a thickness of 1.55 to 1.97 micrometers (T5), and a distance of 20 micrometers from the tip (D20). To the tip with a thickness of 4.60 to 6.34 micrometers (T20), a thickness of 19.80 to 27.12 micrometers (T100) measured at a distance of 100 micrometers from the tip. Has a geometric shape that is continuously tapered toward,
The substrate (10) is covered by a reinforcing coating layer (16) ,
The thickness of the cutting edge (11) of the substrate has the following mathematical formula:
Described by
In formulas (A) and (B), constants a and c have values in the range of (0 to 1), constant b has a value in the range of (0.5 to 1), and constant d is Has a value in the range (0.5-20), x refers to the distance from the tip in micrometers, t refers to the thickness of the blade in micrometers, and equation (A) is the transition point from the tip. A razor blade, which has been applied up to and where either formula (A) or formula (B) has been applied elsewhere . The substrate of claim 1, wherein the substrate has a thickness (T30) of 6.50-8.94 micrometers measured at a distance (D30) of 30 micrometers from the tip (14). Razor blade. 3. The substrate (10) according to claim 1 or 2, characterized in that it has a thickness (T40) of 8.40 to 11.54 micrometers measured at a distance (D40) of 40 m from the tip. Razor blade. The substrate (10) has a thickness (T50) of 10.30 to 14.13 micrometers measured at a distance (D50) of 50 micrometers from the tip. A razor blade according to any one of claims. The substrate (10) has a thickness (T150) of 29.30-40.11 micrometers measured at a distance of 150 micrometers (D150) from the tip. A razor blade according to any one of claims. The substrate (10) has a thickness (T200) of 38.80 to 49.74 micrometers measured at a distance of 200 micrometers (D200) from the tip. A razor blade according to any one of claims. The substrate (10) has a thickness (T250) of 48.30 to 59.37 micrometers measured at a distance (D250) of 250 micrometers from the tip. The razor blade according to any one of claims 1. The substrate (10) has a thickness (T300) of 57.80 to 69.00 micrometers measured at a distance (D300) of 300 micrometers from the tip. A razor blade according to any one of claims. The substrate (10) has a thickness (T350) of 67.30 to 78.62 micrometers measured at a distance (D350) of 350 micrometers from the tip (14). A razor blade according to claim 8. The substrate (10) is mainly iron by weight,
-0.62-0.75% carbon;
-12.7 to 13.7% chromium;
-0.45-0.75% manganese;
-0.20～0.50 percent silicon; and - a razor blade according to any one of claims 1 to 9, characterized in that the unavoidable impurities levels of molybdenum, stainless steel including capital steel. The reinforcing coating layer, razor blade according to any one of claims 1 to 10, characterized in that it comprises titanium and boron. Razor blade according to claim 11 , characterized in that the substrate (10) is covered by an intermediate layer (15), which intermediate layer is covered by the reinforcing coating layer (16). Razor blade according to claim 11 or 12 , characterized in that the reinforcing coating layer is covered by a top layer (20). 14. The razor blade according to claim 13 , wherein the top layer is covered by a polytetrafluoroethylene (PTFE) layer.